this will be used in several places to convert a single TRB into
No-Op. No functional changes in this patch.
Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>
---
drivers/usb/host/xhci-ring.c | 39 +++++++++++++++++++++++++++------------
1 file changed, 27 insertions(+), 12 deletions(-)
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index edb5fcc5a12b..f369d97f663d 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -523,6 +523,31 @@ void xhci_find_new_dequeue_state(struct xhci_hcd *xhci,
(unsigned long long) addr);
}
+static void trb_to_noop(union xhci_trb *trb)
+{
+ switch (TRB_FIELD_TO_TYPE(cpu_to_le32(trb->generic.field[3]))) {
+ case TRB_LINK:
+ /* unchain chained link TRBs */
+ trb->link.control &= cpu_to_le32(~TRB_CHAIN);
+ break;
+ case TRB_NORMAL:
+ case TRB_SETUP:
+ case TRB_DATA:
+ case TRB_STATUS:
+ case TRB_ISOC:
+ trb->generic.field[0] = 0;
+ trb->generic.field[1] = 0;
+ trb->generic.field[2] = 0;
+ /* Preserve only the cycle bit of this TRB */
+ trb->generic.field[3] &= cpu_to_le32(TRB_CYCLE);
+ trb->generic.field[3] |= cpu_to_le32(TRB_TYPE(TRB_TR_NOOP));
+ break;
+ default:
+ /* nothing */
+ break;
+ }
+}
+
/* flip_cycle means flip the cycle bit of all but the first and last TRB.
* (The last TRB actually points to the ring enqueue pointer, which is not part
* of this TD.) This is used to remove partially enqueued isoc TDs from a ring.
@@ -534,18 +559,8 @@ static void td_to_noop(struct xhci_hcd *xhci, struct xhci_ring *ep_ring,
union xhci_trb *trb = td->first_trb;
while (1) {
- if (trb_is_link(trb)) {
- /* unchain chained link TRBs */
- trb->link.control &= cpu_to_le32(~TRB_CHAIN);
- } else {
- trb->generic.field[0] = 0;
- trb->generic.field[1] = 0;
- trb->generic.field[2] = 0;
- /* Preserve only the cycle bit of this TRB */
- trb->generic.field[3] &= cpu_to_le32(TRB_CYCLE);
- trb->generic.field[3] |= cpu_to_le32(
- TRB_TYPE(TRB_TR_NOOP));
- }
+ trb_to_noop(trb);
+
/* flip cycle if asked to */
if (flip_cycle && trb != td->first_trb && trb != td->last_trb)
trb->generic.field[3] ^= cpu_to_le32(TRB_CYCLE);
--
2.11.0
--
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